darthcamaro writes "Traditional thinking has it that you need air conditioning or cold water to cool data center servers right? Well the U.S. Government in partnership with HP now has a new idea — they are going to use warm water to cool servers.
The classic data center has lots of cold air that is approximately 60 degrees supplied to the front of the racks, in an effort to help keep your chips from getting hotter than 150 degrees," Hammond said. "Then you get 80 degree hot air out of the back of the racks and you try to eject that heat and declare victory."
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The NREL (National Renewable Energy Laboratory) approach will supply water that is approximately 75 degrees and then after running through the servers, will return water that is 95 degrees. That return water will then be the primary heating source for the building.